As for the 6th definition of Cant (noun), Merriam Webster

states: Definition

of cant 1: affected singsong or

whining speech; a beggar’s cant 2a :

the private language of the underworld; the cant of

thieves b obsolete: the phraseology peculiar to a religious class or sect. So naturally the term cant is an obsolete noun.

(First answer from this site, hope it helps)